I'm honestly really confused about the specific role docker is playing here. What, exactly, is Docker doing? Is it compiling the application? Is it making a

I'm honestly really confused about the specific role docker is playing here. What, exactly, is Docker doing? Is it compiling the application? Is it making a runtime for the wasm binary? Is it being the runtime for the wasm binary, so the end user builds through whatever usual build processes and gets a binary they can then easily run? If the wasm binary is lightweight and portable, why is docker useful? edit: Given the other comments about "what problem does this solve" I think maybe the blog post has missed its mark slightly